Define a class Rectangle with all required instance variable with appropriate data type

1. Define a class Rectangle with all required instance variable with appropriate data types. Write all set and get methods, area and perimeter, in addition to use defined constructor(s).
   Also write a constructor that will work as a default constructor.

2. Develop a Java application that will sue the class Rectangle and create two rectangle objects using constructors. Show that you understand the manipulation of the rectangle objects using set and get method, printing the area, and perimeter of the rectangle etc.

this is what i could do but i need more help

class FindRectangleArea
{
    public static void main(String arg[])
    {
        Rectangle rect = new Rectangle(11, 5);
        
        System.out.println("Length = " + rect.length);
        System.out.println("Breadth = " + rect.breadth);
        System.out.println("Area = " + rect.getArea());
        System.out.println("Perimeter = " + rect.getPerimeter());
    
    }
}

class Rectangle
{
    double length;
    double breadth;

    Rectangle(double length, double breadth)
    {
        this.length = length;
        this.breadth = breadth;
    }

    double getArea()
    {
        return length * breadth;
    }

    double getPerimeter()
    {
        return 2 * (length + breadth);
    }
}

no.2

package testrectangle;

class Rectangle{
    
    double length, width;

    Rectangle()
    
    {
        length = 1;
        
        width = 1;
        
    }
    
    
    Rectangle(double length, double width)
            
            
    {
        this.length = length;
        
        this.width  = width;
        
    }
    
    // define a method
    double getArea()
            
    {
        return (length * width);
        
    }
    
    double getPerimeter()
            
    {
        return (2 * (length + width));
    }
}
public class TestRectangle {

    public static void main(String[] args) {
        
        
        Rectangle rect1 = new Rectangle();
        
        
        Rectangle rect2= new Rectangle(15.0,8.0);
        
        System.out.println("Area of first object="+rect1.getArea());
        
        System.out.println("Perimeter of first object="+rect1.getPerimeter());
        
        System.out.println("Area of second object="+rect2.getArea());
        
        System.out.println("Perimeter of second object="+rect2.getPerimeter());
   }
    
}

You're really close. Hopefully this helps. Look into the use of toString(), method overriding and String.format, or just replace it with String concatenation in the Application class if you're out of your comfort zone. If this is something you're going to submit, make sure you understand it in full.

// Part 1
// "Define a class Rectangle with all required instance variable with appropriate data types"
public class Rectangle {
private int length;
private int breadth;
// "Also write a constructor that will work as a default constructor."
public Rectangle(){
}
// "in addition to use defined constructor(s)"
public Rectangle(int length, int breadth){
this.length = length;
this.breadth = breadth;
}
// "Write all set and get methods"
public int getLength() {
return length;
}
public void setLength(int length) {
this.length = length;
}
public int getBreadth() {
return breadth;
}
public void setBreadth(int breadth) {
this.breadth = breadth;
}
// "area and perimeter"
public int getArea(){
return length * breadth;
}
public int getPerimeter(){
return (length + breadth) * 2;
}
@Override
public String toString() {
return String.format("length [%s], breadth [%s], area [%s], perimeter [%s]", length, breadth, getArea(), getPerimeter());
}
}
// Part 2
// "Develop a Java application that will sue the class Rectangle."
public class Application {
public static void main(String[] args) {
//" and create two rectangle objects using constructors"
Rectangle rectangle1 = new Rectangle(1, 1);
Rectangle rectangle2 = new Rectangle(5, 10);
System.out.println(rectangle1);
System.out.println(rectangle2);
// "Show that you understand the manipulation of the rectangle objects using set and get method, printing the area, and perimeter of the rectangle etc."
rectangle1.setLength(20);
rectangle1.setBreadth(30);
System.out.println(rectangle1);
}
}